An exhaust system conducts hot exhaust gases generated by an engine through various exhaust components to reduce emissions and control noise. The exhaust system includes an injection system that injects a reducing agent, such as a solution of urea and water for example, upstream of a selective catalytic reduction (SCR) catalyst. A mixer is positioned upstream of the SCR catalyst and mixes engine exhaust gases and products of urea transformation.
In one example configuration, the mixer connects an upstream exhaust component such as a diesel oxidation catalyst (DOC) and/or a diesel particulate filter (DPF) to the SCR catalyst. A doser typically sprays the urea into the exhaust stream upstream of the SCR catalyst. In one known configuration, the doser is mounted to an outer peripheral surface of the mixer and is configured to direct the spray into an exhaust gas stream; however, these known spray configurations can result in increased urea deposit formation, which is undesirable.